Table 2. Pattern of failure and the first failure.
| Parameters | N (%) | χ2 values | p values | ||
|---|---|---|---|---|---|
| All (N = 112) | Early PORT (N = 41) | Late PORT (N = 71) | |||
| LR as first site of failure | |||||
| Yes | 21 (18.8) | 6 (14.6) | 15 (21.1) | 0.72 | 0.40 |
| No | 91 (81.2) | 35 (85.4) | 56 (78.9) | ||
| All LR failure | |||||
| Yes | 24 (21.4) | 8 (39.0) | 16 (22.5) | 0.14 | 0.71 |
| No | 88 (78.6) | 33 (61.0) | 55 (77.5) | ||
| DM as first site of failure | |||||
| Yes | 39 (34.8) | 13 (31.7) | 26 (36.6) | 1.56 | 0.21 |
| No | 73 (65.2) | 28 (68.3) | 45 (63.4) | ||
| All DM failure | |||||
| Yes | 44 (39.3) | 13 (31.7) | 31 (43.7) | 1.56 | 0.21 |
| No | 68 (60.7) | 28 (68.3) | 40 (56.3) | ||
| Both LR and DM as first site of failure | |||||
| Yes | 10 (8.9) | 3 (7.3) | 7 (9.9) | 0.21 | 0.65 |
| No | 102 (91.1) | 38 (92.7) | 64 (90.1) | ||
| Both LR and DM failure | |||||
| Yes | 18 (16.1) | 5 (12.2) | 13 (18.3) | 0.72 | 0.39 |
| No | 94 (83.9) | 36 (87.8) | 58 (81.7) | ||
| Site of DM† | |||||
| Lung | 20 (17.9) | 7 (17.1) | 13 (18.3) | - | - |
| Bone | 14 (12.5) | 3 (7.3) | 11 (15.5) | ||
| Lung pleura | 7 (6.3) | 3 (7.3) | 4 (5.6) | ||
| Central nervous system | 6 (5.4) | 2 (4.9) | 4 (5.6) | ||
| Adrenal gland | 4 (3.5) | 1 (2.4) | 3 (4.2) | ||
| Liver | 4 (3.5) | 2 (4.9) | 2 (2.8) | ||
| Others | 6 (5.4) | 1 (2.4) | 5 (7.0) | ||
Note: some patients had more than one site of LR or/and DM failure at the same time.
PORT: postoperative radiotherapy; LR: locoregional recurrence; DM: distant metastasis.
†Fifteen patients concurrent with multiple metastases including lung, bone, lung pleura, central nervous system, adrenal gland, liver, or others.